Treadmill Incline ↔ Pace Calculator
Convert treadmill pace at an incline to the flat pace of equal effort, and back
What is a Treadmill Incline ↔ Pace Calculator?
Running on a treadmill incline is harder than running on a flat surface at the same speed. This calculator converts between a treadmill pace at a given incline and the flat pace that takes about the same effort, so you can compare hill sessions with flat runs.
It uses the Minetti et al. (2002) model of the energy cost of running on slopes. The cost per metre on a gradient i (as a fraction, 5% = 0.05) is Cr = 155.4i⁵ − 30.4i⁴ − 43.3i³ + 46.3i² + 19.5i + 3.6 (J/kg/m), and the flat-equivalent speed is the treadmill speed × Cr ÷ 3.6.
Worked example: running at 6:00 min/km on a 5% incline costs about 30% more energy than flat running at the same speed, so it is roughly like running 4:37 min/km on a flat road. Use it as a guide to effort, not as an exact prediction of race pace.
How to Use This Calculator
Why Incline and Pace Conversion Matters
Treadmill hill workouts are a great way to build strength, but pace alone is misleading on a slope. A slower pace at 5% incline can be the same effort as a fast flat pace, so converting helps you pick sensible targets and compare sessions.
It also works the other way around. If you know the flat pace you want to train at in effort terms, the calculator shows the treadmill pace to set at different inclines, which helps when you are planning hill intervals.
The model is based on energy cost at steady speeds. Real-life effort also depends on fitness, running form, fatigue and how the treadmill is calibrated. A 1% incline is often used to make treadmill running feel like outdoor running because it offsets the lack of air resistance, and that small effect is not included here.
?Frequently Asked Questions
In the model, a 1% incline raises the energy cost of running by about 5-6% at the same speed. Separately, runners often set the treadmill to 1% to roughly offset the lack of air resistance indoors (Jones and Doust, 1996). This calculator does not include that air-resistance effect.
It is the flat-ground pace that takes about the same energy as your current pace on an incline. A 6:00 min/km pace at 5% incline is about as hard as roughly 4:37 min/km on a flat surface.
No. In the model, a 5% decline lowers the energy cost by about 24%, while a 5% incline raises it by about 30%, so the saving is smaller than the cost. Real downhill running also loads your legs differently, so treat declines as a rough guide. The calculator accepts declines down to −10%.
It is an estimate based on a published model of energy cost at steady speeds. Fitness, fatigue, form and the treadmill's own calibration all affect real effort, so use it to compare sessions and plan hill workouts rather than to predict race times.
The table shows the treadmill pace that gives the same effort at different inclines, so you can plan a session where the incline changes between intervals without changing your effort.